setPrecedenceStartState method

void setPrecedenceStartState(int precedence, DFAState startState)

Set the start state for a specific precedence value.

@param precedence The current precedence. @param startState The start state corresponding to the specified precedence.

@throws IllegalStateException if this is not a precedence DFA. @see #isPrecedenceDfa()

Implementation

void setPrecedenceStartState(int precedence, DFAState startState) {
  if (!isPrecedenceDfa()) {
    throw StateError(
        'Only precedence DFAs may contain a precedence start state.');
  }

  if (precedence < 0) {
    return;
  }

  // synchronization on s0 here is ok. when the DFA is turned into a
  // precedence DFA, s0 will be initialized once and not updated again
  // s0.edges is never null for a precedence DFA
  if (precedence >= s0!.edges!.length) {
    final original = s0!.edges!;
    s0!.edges = List.filled(precedence + 1, null);
    List.copyRange(s0!.edges!, 0, original);
  }

  s0!.edges![precedence] = startState;
}